Deflection is a tactic that forces an opponents piece to leave the square, row or file where it has to remain, because it is needed there to defend something.
Deflection Lesson - From ChessGuru.net
Chess Quiz - Problems 5,6,7 All use Deflection as a solution (Answers at bottom of page)
Video Deflection Lesson
Hans Berliner, 1929-2017
3 days ago